There are numerous types of Uninterruptible Power Supply (UPS) systems that supply backup alternating current (AC) or direct current (DC) power to one or more electrical loads. These UPS systems generally use batteries or types of other energy storage devices that supply such power when a main power supply (e.g., line power) is not available. For example, backup power is provided when power from an AC source performs outside acceptable limits or fails altogether.
These UPS systems generally use multiple energy storage devices configured in parallel or in series to provide backup power. Due to varying power supply requirements of the equipment being powered by the UPS, there is a need to have a UPS system that is modular and can be tailored to meet the power supply requirements to one or more electrical loads. There are several different UPS systems that include modular components such as battery modules and power modules. Battery modules generally provide DC power for conversion by the UPS system to the necessary output power, and power modules accept battery power and perform the appropriate conversion depending on the output requirements.
U.S. Pat. No. 6,310,783 describes one such type of modular UPS chassis that accepts one or more battery modules (or packs) and power modules. In this system, a slot of the chassis can accept either a battery module or power module allowing a more flexible UPS system to be constructed with varying numbers of power modules and battery modules.
There are a number of modular UPS systems that are commercially available. These existing modular UPS systems include replaceable power modules and battery modules provided in a frame, and these systems are each built and tested individually at the factory as a complete system. These UPS systems are generally custom-ordered by a customer and are provided in a variety of configurations. Such modular UPS systems are commercially-available from a variety of vendors including the American Power Conversion Corporation (APC) of West Kingston, R.I.